Direct synthesis of functionalized PCN-333 via linker design for Fe3+ detection in aqueous media

Abstract

A new luminescent mesoporous metal–organic framework (PCN-604) was successfully synthesized from trimetric clusters, Al₃(O)(CH₃COO)₆, and pyridine-based tritopic linkers, 4,4′,4′′-(pyridine-2,4,6-triyl)tribenzoate (PTB), via a solvothermal reaction. The MOF with an MTN topology possesses remarkable aqueous and thermal stabilities. Due to the efficient binding sites rendered by the pyridyl-based linkers, PCN-604 shows a fast fluorescence response towards trace amounts of Fe³⁺ ions in water in a fluorescence-quenching mode. The Stern–Volmer quenching constant is calculated to be 8.53 × 10³ M⁻¹ and the limit of detection is 6.2 μM, which convincingly demonstrate the ability of the MOF for Fe³⁺ detection.